The Brazilian superstar had a hand in everything else his new side did at the Parc des Princes as they recovered from the shock of falling.
The Brazilian superstar had a hand in everything else his new side did at the Parc des Princes as they recovered from the shock of falling behind early on to a Max Gradel goal.
Neymar got the equaliser and the 222 million-euro ($261 million) man later completed the rout in stunning style after further goals from Adrien Rabiot, an Edinson Cavani penalty, Javier Pastore and Layvin Kurzawa.
Marco Verratti was sent off for PSG midway through the second half and Toulouse at one point came back to 3-2, but they were ultimately blown away by the world's most expensive player.
"I feel very happy and relaxed, I feel at home. I am adapting as quickly as possible. I am getting better physically and I can still improve yet," the 25-year-old said ominously after the game.
It was PSG's third win in as many league outings this season and they join reigning champions Monaco and Saint-Etienne in having the maximum nine points to their name.
Saint-Etienne visit the French capital next Friday and will be dreading the prospect after this latest exhibition from PSG's new superstar.
Neymar had a part in all of his side's goals in last week's 3-0 win at Guingamp, scoring one in his first game in French football since his stunning world-record transfer, and he was again at the centre of everything here.
Gradel, making his first appearance for Toulouse on loan from Bournemouth, volleyed the away side in front in the 18th minute but Neymar had already seen a shot strike the top of the bar before that.
The Brazilian then saw a header tipped onto the post by Alban Lafont before he equalised just after the half-hour, setting up Rabiot for a shot that was pushed out by the away goalkeeper before following in to convert the loose ball.
The same duo combined as PSG went in front, Rabiot playing a one-two with Neymar before beating Lafont with a low strike into the bottom corner from 25 yards.
The second half was quieter before coming to life after Verratti was harshly shown a second yellow for catching Christopher Jullien in the Toulouse area in the 69th minute.
Soon after, the referee gave a harsh decision the other way, awarding a penalty for a foul on Neymar when Toulouse striker Andy Delort appeared to play the ball.
Cavani scored from the spot, the goal his 11th in his last 11 Ligue 1 games, but Toulouse quickly pulled another one back when the giant Jullien headed in from a corner with 12 minutes left to make it 3-2.
Yet there was to be no grandstand finish from the visitors, as instead substitute Pastore -- the man who has lost his place to accommodate Neymar -- curled in a superb fourth.
Neymar's corner was headed in by Kurzawa. But Neymar had to have the last word and somehow engineered himself space in the area in stoppage time before finishing to make it 6-2 and bring the Parc des Princes crowd to its feet.
"If I forget the fact I am the Toulouse coach, it is good for football to see that kind of class," said opposition boss Pascal Dupraz.
Elsewhere on Sunday, Marcelo Bielsa suffered a second straight loss as Lille coach in a disappointing 2-0 home defeat against Caen, while Marseille were frustrated by Angers in a 1-1 draw at the Velodrome.
Radamel Falcao struck his fifth goal in three games on Friday to give Monaco a 1-0 win at Metz, while Saint-Etienne beat newcomers Amiens 3-0 on Saturday.